package com.white.hot.utils;

import java.security.MessageDigest;

public class MD5Util
{

    private static String byteArrayToHexString(byte b[])
    {
        StringBuffer resultSb = new StringBuffer();
        for (int i = 0; i < b.length; i++)
            resultSb.append(byteToHexString(b[i]));

        return resultSb.toString();
    }

    private static String byteToHexString(byte b)
    {
        int n = b;
        if (n < 0)
            n += 256;
        int d1 = n / 16;
        int d2 = n % 16;
        return hexDigits[d1] + hexDigits[d2];
    }

    public static String MD5Encode(String origin, String charsetname)
    {
        String resultString = null;
        try
        {
            resultString = new String(origin);
            MessageDigest md = MessageDigest.getInstance("MD5");
            if (charsetname == null || "".equals(charsetname))
                resultString = byteArrayToHexString(md.digest(resultString.getBytes()));
            else
                resultString = byteArrayToHexString(md.digest(resultString.getBytes(charsetname)));
        } catch (Exception exception)
        {
        	return null;
        }
        return resultString;
    }

    public static String soltMd5(String id)
    {
        String md5Str = id + MD5Encode(id, "ISO-8859-1") + id;
        return MD5Encode(md5Str, "UTF-8");
    }

    public static String simpleSoltMd5(String id)
    {
        String md5Str = id + "X3C";
        return MD5Encode(md5Str, "UTF-8");
    }

    private static final String hexDigits[] = {"0", "1", "2", "3", "4", "5",
            "6", "7", "8", "9", "A", "B", "C", "D", "E", "F"};

}
